In 1005, still with her fleet engaged in Sicilian waters, the Arab pirates fell upon her, and, forcing the harbour, sacked a whole quarter of the city. For the time Pisa could do little against the foes of Europe, but in 1016 she allied herself with that city which proved at last to be her deadliest foe, Genoa the Proud, and the united fleets swept down on Sardinia for vengeance. It was this victorious expedition that aroused the hatred of the Pisans for Genoa, a jealousy that was only extinguished when at last Pisa was crushed at Meloria. Many were the attempts of the Arabs to regain Sardinia, but Pisa was not to be deceived. Coasting along the African shore, her fleet took Bona and threatened Carthage. Yet in 1050 the Arabs of Morocco and Spain stole the island from her, only Cagliari holding out under the nobles for the mother city. There was more than the loss of Sardinia at stake, for with the victory of the Arabs the highway of the sea was no longer secure, the existence of Pisa, and not of Pisa only, was threatened. So we find Genoa once more standing beside Pisa in the fight of Europe. The fleets again were combined, this time under the command of a Pisan, one Gualduccio, a plebeian. He sailed for Cagliari, landed his men, and engaged the enemy on the beach. The Arabs were led by the King Mogahid, Re Musetto, as the Italians called him. He was over eighty years old at the time, and though still full of cunning valour, attacked by the fleets in front and the garrison in the rear, his army was defeated and put to flight. He himself, fleeing on horseback, was wounded in two places, and falling was captured; and they took him in chains to Pisa, where he died. Thus Sardinia once more fell into the hands of Europe, and the island, divided in fiefs under the rule of Pisa,[18] was held and governed by her. But Pisa was not yet done with the Arab. She stood for Europe. In 1063 she fought at Palermo, returning laden with booty. It was then, after much discussion in the Senate,[19] sending an embassy to the Pope and another to "Re Henrico di Germania," that she decided to employ this spoil in building the Duomo, in the place where the old Church of S. Reparata stood, and more anciently the Baths of Hadrian, the Emperor. The temple, Tronci tells us,[20] was dedicated to the Magnificent Queen of the Universe, Mary, ever Virgin, most worthy Mother of God, Advocate of sinners. It was begun in 1064, and many years, as Tronci says, were consumed in the building of it.[21] The pillars--and there are many--were brought by the Pisans from Africa, from Egypt, from Jerusalem, from Sardinia, and other far lands.